International Klein Blue

#051FAF

About International Klein Blue

International Klein Blue, often abbreviated as IKB, is a deep blue hue first mixed by the French artist Yves Klein. Klein patented this color in 1957, giving it a unique status in the art world. IKB's striking visual impact comes from its high saturation and luminosity, creating a vivid and almost overwhelming impression on the viewer. The color is intended to evoke a sense of boundlessness and spirituality, qualities Klein sought to express in his monochrome paintings. Its unique formulation involves a synthetic ultramarine pigment suspended in a clear resin binder, which preserves the pigment's brilliance. Because of its intensity and historical significance, IKB remains a powerful and recognizable color choice in art, design, and culture.

The color #051FAF, also known as International Klein Blue, presents some accessibility challenges, especially for users with visual impairments. Its low luminance value of approximately 3% means that text rendered in this color requires very light foreground colors to achieve sufficient contrast. According to WCAG guidelines, a contrast ratio of at least 4.5:1 is needed for normal text and 3:1 for large text. Using white (#FFFFFF) as a foreground color with #051FAF yields a contrast ratio of approximately 14.7:1, which comfortably meets accessibility standards. However, using mid-tone grays or colors close to #051FAF will likely result in insufficient contrast, making content difficult or impossible to read. Designers should carefully evaluate color combinations and utilize contrast checking tools to ensure compliance with accessibility standards, benefiting users with low vision or color blindness.

Shades

Digital Color Formats

RGB
5 31 175
RGB5 31 175
Red
Green
Blue
HSL
230.82 94.44% 35.29%
230.8294.4435.29HSL
Hue
Saturation
Lightness
HWB
230.82 1.96% 31.37%
230.821.9631.37HWB
Hue
Whiteness
Blackness
hex#051FAF
rgb5 31 175
hsl230.82 94.44% 35.29%
cmyk97.14% 82.29% 0% 31.37%
hwb230.82 1.96% 31.37%
xyz8.29 4.11 40.91
CMYK
97.14% 82.29% 0% 31.37%
97.1482.29031.37CMYK
Cyan
Magenta
Yellow
Key
XYZ
8.29 4.11 40.91
8.294.1140.91XYZ
X
Y
Z

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